Breast reconstruction implant

Abstract

Absorbable implants can be used to create volume and shape in the breast of a patient with regenerated tissue. The implants comprise scaffolds formed from layers of parallel filaments. The layers of filaments can be stacked and bonded together to form scaffolds with porous crisscross arrangements of filaments. The implant's scaffolds may be coated or filled with cells and tissues, including autologous fat graft, and/or a vascular pedicle may be inserted into the implant. The implants are particularly suitable for use in plastic surgery procedures, for example, to regenerate or augment breast tissue following mastectomy or in mastopexy procedures, and can provide an alternative to the use of permanent breast implants in these procedures.

We claim: 
     
       1. A breast implant comprising a porous three-dimensional scaffold, wherein the implant comprises a back area for placement on the chest wall of a patient, a front area opposite the back area, the front area comprising a front bottom for placement in the lower pole of the breast, a front top for placement in the upper pole of the breast, and a front intermediate-region for placement under the skin of the patient, wherein the implant has a compressive modulus of 0.1 kPa to 10 MPa, wherein the scaffold comprises at least two adjacent parallel planes of filaments bonded to each other, and wherein the filaments in each plane extend in the same direction. 
     
     
       2. The implant of  claim 1 , wherein the front bottom of the implant has a convex exterior surface. 
     
     
       3. The implant of  claim 1 , wherein the parallel planes of filaments are formed with a polymer, and wherein the polymer has one or more of the following properties: (i) an elongation at break greater than 100%; (ii) an elongation at break greater than 200%; (iii) a melting temperature of 60° C. or higher, (iv) a melting temperature higher than 100° C., (v) a glass transition temperature of less than 0° C., (vi) a glass transition temperature between −55° C. and 0° C., (vii) a tensile modulus less than 300 MPa, and (viii) a tensile strength higher than 25 MPa. 
     
     
       4. The implant of  claim 1 , wherein the implant has a loss modulus of 0.3 to 100 kPa. 
     
     
       5. The implant of  claim 2 , wherein the convex exterior surface approximates the anatomical feature of the lower pole of a breast. 
     
     
       6. The implant of  claim 1 , wherein at least two parallel planes of filaments have the same orientation in adjacent planes or nonadjacent planes. 
     
     
       7. The implant of  claim 1 , wherein a first parallel plane of filaments is organized in a first geometrical orientation, and a second parallel plane of filaments is arranged in a second geometrical orientation such that a porous scaffold of crisscrossed filaments is formed through the scaffold. 
     
     
       8. The implant of  claim 7 , wherein the scaffold further comprises a third parallel plane of filaments, and the filaments in the first, second and third parallel planes form pores with a triangular shape. 
     
     
       9. The implant of  claim 1 , wherein an angle between the filaments in the parallel planes is selected from one of the following: between 1 and 120 degrees, or 18, 20, 30, 36, 45 or 60 degrees. 
     
     
       10. The implant of  claim 1 , wherein the scaffold further comprises a plurality of hollow channels. 
     
     
       11. The implant of  claim 10 , wherein the channels have a diameter greater than 100 microns. 
     
     
       12. The implant of  claim 1 , wherein the filaments have one or more of the following properties: an average diameter or average width of 10 μm to 5 mm, a breaking load of 0.1 to 200 N, an elongation at break of 10 to 1,000% or 25 to 500%, and elastic modulus of 0.05 to 1,000 MPa or 0.1 to 200 MPa. 
     
     
       13. The implant of  claim 1 , wherein the at least two parallel planes of filaments are bonded together by 3D printing the filaments. 
     
     
       14. The implant of  claim 1 , wherein an infill density of filaments in the scaffold is selected from one of the following: between 1% and 60%, or between 5% and 25%. 
     
     
       15. The implant of  claim 1 , wherein the implant further comprises a shell or coating at least partly surrounding the parallel planes of filaments. 
     
     
       16. The implant of  claim 15 , wherein the shell has an outer surface and an inner surface that surrounds an interior volume of said shell. 
     
     
       17. The implant of  claim 15 , wherein the shell comprises a stack of concentric filaments. 
     
     
       18. The implant of  claim 1 , wherein the implant is absorbable. 
     
     
       19. The implant of  claim 1 , wherein the compressive modulus decreases, within 2 years from being implanted, to less than or equal to 200 kPa. 
     
     
       20. The implant of  claim 1 , wherein the implant is configured to recover at least 50%, 70%, or 90% of its original volume upon application and subsequent removal of a compressive force. 
     
     
       21. The implant of  claim 1 , wherein the implant has a compression resilience between 1-80%. 
     
     
       22. A method of manufacturing a breast implant comprising a porous three-dimensional scaffold, wherein the implant comprises a back area for placement on the chest wall of a patient, a front area opposite the back area, the front area comprising a front bottom for placement in the lower pole of the breast, a front top for placement in the upper pole of the breast, and a front intermediate-region for placement under the skin of the patient, wherein the implant has a compressive modulus of 0.1 kPa to 10 MPa, and wherein the scaffold comprises at least two adjacent parallel planes of filaments bonded to each other with the filaments in each plane extending in the same direction, wherein the method comprises forming a scaffold by one of the following (i) forming at least two parallel planes of filaments from a polymeric composition by 3D printing of the filaments, and (ii) forming at least two parallel planes of filaments from a polymeric composition by melt extrusion deposition printing. 
     
     
       23. The method of  claim 22 , wherein the front bottom of the implant has a convex exterior surface. 
     
     
       24. The method of  claim 22 , wherein the polymeric composition is selected from a polymer or copolymer comprising, or prepared from, one or more of the following monomers: glycolide, lactide, glycolic acid, lactic acid, 1,4-dioxanone, trimethylene carbonate, 3-hydroxybutyric acid, 3-hydroxybutyrate, 3-hydroxyhexanoate, 3-hydroxyoctanoate, 4-hydroxybutyric acid, 4-hydroxybutyrate, ε-caprolactone, 1,4-butanediol, 1,3-propane diol, ethylene glycol, glutaric acid, malic acid, malonic acid, oxalic acid, succinic aid, and adipic acid, or wherein the polymeric composition comprises poly-4-hydroxybutyrate or copolymer thereof, or poly(butylene succinate) or copolymer thereof. 
     
     
       25. The method of  claim 22 , wherein the filaments are formed with a polymer, and wherein the polymer has one or more of the following properties: (i) an elongation at break greater than 100%; (ii) an elongation at break greater than 200%; (iii) a melting temperature of 60° C. or higher, (iv) a melting temperature higher than 100° C., (v) a glass transition temperature of less than 0° C., (vi) a glass transition temperature between −55° C. and 0° C., (vii) a tensile modulus less than 300 MPa, and (viii) a tensile strength higher than 25 MPa. 
     
     
       26. The method of  claim 22 , wherein the filaments have one or more of the following properties: (i) average diameter or average width of 10 μm to 5 mm, (ii) breaking load of 0.1 to 200 N, 1 to 100 N, or 2 to 50 N, (iii) an elongation at break of 10 to 1,000% or 25 to 500%, or greater than 100% or 200%, (iii) elastic modulus of 0.05 to 1,000 MPa or 0.1 to 200 MPa. 
     
     
       27. The method of  claim 22 , wherein the scaffold has a loss modulus of 0.1 kPa to 5 MPa. 
     
     
       28. The method of  claim 22 , further comprising:
 compressing the implant with a compressive force; and 
 removing the compressive force from the implant, wherein the implant is configured to recover at least 50%, 70%, or 90% of its original volume after removal of the compressive force. 
 
     
     
       29. The method of  claim 22 , wherein the implant has a compression resilience between 1-80%.